Christmas rail travellers may have to change their plans if guards and drivers on South West Trains opt for strike action.

The company, which operates an hourly service from Brighton to Reading, is facing action from guards and station staff after its drivers, represented by their union ASLEF, were given a 7.5 per cent increase.

Strikes could begin on Christmas Eve and hit rail services throughout the festive season.

It would mean travellers from Brighton and stations to Reading, via Gatwick, having to make alternate arrangements. The company also runs a service from Waterloo to Horsham.

Guards and station staff belonging to the Rail Maritime and Transport Union (RMT) have rejected a pay offer of four per cent and are holding out for a bigger deal.

The RMT is also in dispute over the disciplining of two of its officials and has accused South West Trains of being heavy-handed with workers.

Thousands of RMT members will start voting next week in two ballots on pay and discipline, with the results due later this month.

The union will have to give the rail company seven days' notice of any industrial action.